a) one-year-old shoot; b) tip of one-year-old shoot with group of leaves from shostalks a vegetative pear is formed; c) vegetative fruit with rosette of remaining leaves in upper hollow; d) lower part of trunk of scion; e) excrescence on stock

In addition to the varieties described above, I find it absolutely necessary
to give an account of an interesting variety of pear that has been found in
the mountains of North Caucasus.

The Vegetativnaya pear is a matter of outstanding world interest
because in the course of the vegetative period it produces three
cropstwo by sexual means and one by vegetative means, which is never
observed in other perennial fruit plants.

In the summer of 1931 I sent my immediate assistant, Pavel Nikanorovich
Yakoviev, who has thoroughly studied and fully understands the work of
hybridization, to get this pear, and soon after he brought me all the
material and precise information, collected where this pear was
foundin the mountains of North Caucasusthat interested me.

It was ascertained that in the spring, like all other varieties, this
pear blooms and bears fruit of medium size and of fairly good flavour.
After the fruit ripens, in the first half of July, the tree blooms a second
time and simultaneously, the buds on the young shoot give rise to small
stalklike formations which, in their turn, bear several buds at the tips
crowded close together; from these buds leaves begin to develop.

As these leaves grow, their petioles gradually and simultaneously begin
to swell, and by the end of August and beginning of September, when the
pears from the second blooming are already ripening, the fruit that was
formed vegetatively from the petioles also acquires pear shape; and by this
time the petioles are quite imperceptible, because it was from their
simultaneous thickening on the fruit stalks that these fine pears, which
for size and flavour cannot be distinguished from fruit that had set at
blossoming, were formed.

The leaf blades of the petioles from which the "asexual" pears are
formed do not disappear like the stalks; they remain in the place of the
calyx, gracefully protruding from the top of the vegetative fruit in the
form of a large bunch of rosettes (see Fig. 131).

A detailed inspection of the garden where this pear grows revealed that
there were two specimens of this variety of pear at the place and both
proved to be grafted, the scion looking somewhat thinner than the stock and
having a large excrescence above the latter (such an excrescence is often
found on grafted varieties of fruit trees which have a stock of an alien
species).

In addition to cuttings from this vegetative pear, roots were also taken
for the purpose of ascertaining the species of the stock on which this pear
had been grafted, for the possibility was not precluded that all this
mix-up in fruit bearing was due to the influence of the stock.

The cuttings from this exceptionally interesting pear were grafted on
August 11, 1931, in our chief scientific department [the Plant-Breeding and
Genetics Station], on to different species of stock: apple, pear, quince,
mountain ash, service tree and hawthorn.

The excellent way in which the buds took to all kinds of stocks, which
became evident already in September, reveals the enormous plasticity and
adaptability of this pear in respect to joining easily with remote species.

It may be hoped that the Vegetativnaya pear will, in its turn,
either by planting, or by hybridization with other, cultivated varieties of
pears and with other species and genera of fruit plants, produce a number
of excellent varieties that will be capable of bringing about a great
improvement in socialist fruit growing.

The bulletins on the work of the experimental station will give reports
on the results of the experiments made with the Vegetativnaya pear,
and, in particular, on the correlative influence upon it of different
species of stocks.